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x86, bitops: make constant-bit set/clear_bit ops faster, adapt, clean up 

fix integration bug introduced by "x86: bitops take an unsigned long *"
which turned "(void *) + x" into "(long *) + x".

small cleanups to make it more apparent which value get propagated where.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Ingo Molnar 2008-06-20 07:28:24 +02:00
parent 1a750e0cd7
commit 7dbceaf9bb
1 changed files with 22 additions and 14 deletions
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36
include/asm-x86/bitops.h
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@ -28,16 +28,15 @@
#define BITOP_ADDR(x) "+m" (*(volatile long *) (x))
#endif
#define ADDR BITOP_ADDR(addr)
#define ADDR BITOP_ADDR(addr)
/*
* We do the locked ops that don't return the old value as
* a mask operation on a byte.
*/
#define IS_IMMEDIATE(nr) \
(__builtin_constant_p(nr))
#define CONST_MASK_ADDR BITOP_ADDR(addr + (nr>>3))
#define CONST_MASK (1 << (nr & 7))
#define IS_IMMEDIATE(nr) (__builtin_constant_p(nr))
#define CONST_MASK_ADDR(nr, addr) BITOP_ADDR((void *)(addr) + ((nr)>>3))
#define CONST_MASK(nr) (1 << ((nr) & 7))
/**
* set_bit - Atomically set a bit in memory
@ -56,13 +55,17 @@
*/
static inline void set_bit(unsigned int nr, volatile unsigned long *addr)
{
if (IS_IMMEDIATE(nr))
asm volatile(LOCK_PREFIX "orb %1,%0" : CONST_MASK_ADDR : "i" (CONST_MASK) : "memory");
else
asm volatile(LOCK_PREFIX "bts %1,%0" : ADDR : "Ir" (nr) : "memory");
if (IS_IMMEDIATE(nr)) {
asm volatile(LOCK_PREFIX "orb %1,%0"
: CONST_MASK_ADDR(nr, addr)
: "i" (CONST_MASK(nr))
: "memory");
} else {
asm volatile(LOCK_PREFIX "bts %1,%0"
: BITOP_ADDR(addr) : "Ir" (nr) : "memory");
}
}
/**
* __set_bit - Set a bit in memory
* @nr: the bit to set
@ -89,10 +92,15 @@ static inline void __set_bit(int nr, volatile unsigned long *addr)
*/
static inline void clear_bit(int nr, volatile unsigned long *addr)
{
if (IS_IMMEDIATE(nr))
asm volatile(LOCK_PREFIX "andb %1,%0" : CONST_MASK_ADDR : "i" (~CONST_MASK));
else
asm volatile(LOCK_PREFIX "btr %1,%0" : ADDR : "Ir" (nr));
if (IS_IMMEDIATE(nr)) {
asm volatile(LOCK_PREFIX "andb %1,%0"
: CONST_MASK_ADDR(nr, addr)
: "i" (~CONST_MASK(nr)));
} else {
asm volatile(LOCK_PREFIX "btr %1,%0"
: BITOP_ADDR(addr)
: "Ir" (nr));
}
}
/*